SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f5950d716fee7ef19108a1a5405d67edb708c6fbea9604a2340ea37501a29b5' 
  AND token = 'CzMuIykw0XlXj9op6iLv2TNwbBPawYX/eOZTA/gJYCk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00103

JSON explain

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