SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e15ae8d1b79dbf418ce2cf80e51b37e96ff1033fc1d02608beed7b7b31b4d369' 
  AND token = 'eyVenBXJmyxdzhchlxl467gaNxqvi3MTZdEm96miO8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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