SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0a6e6bf4d3435fa2d34c53204410d804872b786723bd79fcdb8a96ae66289de' 
  AND token = 'KfpOGc1ylrnoPvtPTcueg0Q/ySEIElEDOMcPizH4p/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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