SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '227585ef5347e4c683d4ad9aa63fd8179565dcd9e3a1353fd9dc7a3717e81688' 
  AND token = 'NfuQbY8anY8ZFD+zHnABv7HqVS73aqFr6SOrCqgcYno=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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