SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f007d74334b796e30355cc5fbfc66ab89786c302874b89783838e6afe23f7a2a' 
  AND token = 'BdJ1zblosMet6F3FD21mPpZjTqrKZYon6Z60ag+hQLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}