SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f861f4628b9be4c671f485c1d1752dbdf4649a9ec15acc8c64b05937583e55f6' 
  AND token = 'ZTQFJrc46WHcDpHQCUnmTyglwFvC/Dnu/1zQ232/Kb4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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