SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1242cc79ca0dbcd637f711ec746fe060d4bbff5dba5e6ad6b98754f777320e59' 
  AND token = 'xo43PY+EGNoMep1q5awD2djU0oVEH/xeBClhFMQ3Gl4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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