SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a4f32578f6bf15a9d33bbc7472436e66cfb63f5e88916fe16ba1c226620d62e' 
  AND token = 'xxJIvZZVqJ2dO/ChODZwcmvmitX1AB1JOZljOsgabrc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

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