SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84930c9baa8d1449152c081612222365c53197d832c33e8d6c23751de99b1614' 
  AND token = 'PTK80ujwLAF890V+dlXcot2FbY2m7BXW8/9bmTDSNhQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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