SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e458217a0ac281c552735a45b9726fafa39c2260e9b0fe569548610a029021c5' 
  AND token = 'Gr2O8kTjX72f4ovab6yKBwvdjRRzj3ZnWPb5Xl1kPPo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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