SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7fa47cfc475152b37c7896e30a56db8666dab4cb95f23549a04db0c4dfeecce1' 
  AND token = 'YJWjDav/CFjWTcnPOZNcTFWzD/tLbiI66XLh40vInXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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