SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72613c03bfbd432f3a18b61456526d925731a382d00d458f5e9a3a8d484475da' 
  AND token = 'plFj8oWm0Ef3zLkZzCjDnjpZsE2h8mECiLqix7MRgmg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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