SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '071801774e9ca2966888e533c082b6965a112dda324514d405d4132e77196973' 
  AND token = 'MjJuK8GqE9rXwI87w+AvIR7h3+uOUFPrauysOWkWOl0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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