SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd7938a01e07fd27748cdd411ad31bf6b0aef61a92f5d2bd75367fa198be0d9f' 
  AND token = 'JN2/bSKlYxYapSEnJeCWGPs5GxulhS2ZF1VcuVw0p28=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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