SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10090903b50ecdf871cfa9259efd8f56319fddc038bf9b08ce2c06a502d678fe' 
  AND token = 'zIzkj8TyQB2Uq+6LJN1l17F2fGCU7KNeOfhoY/R6tt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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