SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '644f2b92ff8d2d69a2495e78066ca637db05ab3ba95466d2e9e2e9376c1f510c' 
  AND token = 'E+ehU9KL7P6hOPYB8pmqtQrNDpvpBcQAh/RZ4i20/tM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00110

JSON explain

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