SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5feeb4491c1b7fb69264f4b2ef0f45fad1bdcba6a6b75462c84205cd44dbd4e5' 
  AND token = 'YrDNjSRy8wYL5oqNxW4yJLKNSEYP8+jEoE3vZbXNmUY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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