SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3112bfbb4480fa4d89932356657bcd7f22fadf3b1c8dea532f215f47a626b786' 
  AND token = 'GI40v9ohyZbUufYp5PMDGFKF7j+TvzOJjbKg57W6rUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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