SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '75233b41c5565612e10d3245edfdd61bbc76a5cdaf4d813d2db5cba37259a3d7' 
  AND token = 'zJNVPVdQOX+jTlc05qbd+YXYqRFtGUfNCsgSmHIdTPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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