SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f268d2d9936a51301adaa8d697e8bff56044bdd04f2285cb6cc053174a16ab40' 
  AND token = 'Xeg70kh4fXEIv8qshFeeBQ37JNkOU2OgcoS0xcC3HOQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}