SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49fad792c23c66af5d3242d0179cd8ba4c95b8e9e69e086283a9e6dc5d4b7cc5' 
  AND token = 'W3dNUQLOyvnflzuHXcUKRlKBsqLRpWopA6uDvo/Ep6Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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