SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7a99ea30dfaf3805706385275b30336fbacdd3abfad79e5b4448d4c285bd0e91' 
  AND token = 'kD+8QXElzVD/U1VbyPFj/w6tvX39tOejBxcmuHFuY8Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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