SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4c35409627bfefa65f2d369c17558648cd8ed6591458d8da2a0479dca251cdf' 
  AND token = 'GSM725CL22U01nn+ogZI8Bywk14XZrDv/QoJOdik4r4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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