SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ba85a2057f3fc8bf0f763e6c233b543459d7132859a6ae2cac558bc4cc15e87' 
  AND token = 'DzUbJbeHZpJUTK2TZ5fU7/KjWvS8DqRW7hCv51hGhss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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