SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ca98f5ab4a2f5f8cd53974e03420f192f17158efbdeb46e3490e50e290db560' 
  AND token = '1DRLLHbWXA1kxhtWVM173CCk+Vj2C/3kmejRqpWOnwM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}