SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3778179e43b96756ef869cdb926d0519b54c6d0b33d134b26c56c9ba502e2eb6' 
  AND token = 'O8xG1UyG2hG/Ur18tamBPjuY8Rqfwdk/+h5Ieln4sME=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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