SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58d3286853809c65889d8f8dc1468ed6b0f2573b70cc29fb3233e69d7379b557' 
  AND token = '6b064hvAPSHUvSMliO5e+Osq/QGzciWiPMtAvMzbL5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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