SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5725cd344db727cd706e87d4e7f82268387b04497bbe56e9a285df0b6184679' 
  AND token = 'W/fI2qpYhpWkZH+3Wwh+n4J0ip6jCPIRz7O2zCSyKC4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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