SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'adac0e7f6a8693eb2e70b1e3cade8ad72f3c47749d354a9fdc5065f835d9e5f4' 
  AND token = 'waJ+hc5Kv9ZNm5CYD/zcf9wzh6HPeofD/eduulSVbUk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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