SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef0a6fa73f52ddfc2cf50fa093969252229eaaa2b6ffa5673ceedcbe82b21068' 
  AND token = 'U4t0qUGnb2RkUuR153eUBlvJm7c8i/HOYtklKmjWcSs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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