SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a94c3e64f3934180af67baa17a4012474298ab4d5c085e3105a7e0d1c17b59b1' 
  AND token = 'JI0gFiYia8RKrALp3ClOinl5biIx4/NvVnRggbgHMtE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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