SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fdde21fb4377b1de183c06c478e86eeb5fc32dad554be3db330fd4c5350d8a8' 
  AND token = 'HQ0cShSWl/7LicGrythZgMyLO3BFqeCDOOXbt7Tq2kM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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