SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '181b2fd1878873da1141a4afa03f662670c51a45e2fc97074b3e86554470dd5a' 
  AND token = 'o9UfzcDNCNLbElDpzcgKnTOj0cf3Ss1hDqFacZ9/M70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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