SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b2ba65156fc16102203fdf21e510ea1545c02606d5edbd1e9c59429c53704d0' 
  AND token = 'rmPPUABNhLKnlsBXYr2x0Xb1znqT7Jxwso2ODp5fHUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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