SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac662e5f0b0da4ef97560254ffb1096798fd22e19d843791753f1ad8b410559d' 
  AND token = 'A9r8h+5dlq4RKlv8gBJcJscIJz6Mu/RT0vdot4VMwCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}