SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e02c3354985435d6c2963cd064eb5cbb7bafa73fec498efc751850d17b283dcc' 
  AND token = 'vI56rKQvu5/TIDCuGizih9y8Zp0QqxgbtN+KfdcGr/4=' 
  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"
    }
  }
}