SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f14228de719e02d6a302a2324e19475201dce23f630f71eb7b6bc35a6cb6c31e' 
  AND token = '5YEDrPVU5mrBHApILJ4fayelXR6VALZwzj6A+Z8S2iQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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