SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f01ff9224168bf76904377ea8a0a18ef1b1092b842527d47587616df61248c1' 
  AND token = 'ptzgiAnVKsGT5KSLUq8gKuemGYcKrNUlYcx8cPgb6hU=' 
  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"
    }
  }
}