SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8424f28cb7f855cac01cc2ec39cf34717d09dca0725cf36487126b0aad4e62b' 
  AND token = '0HZuXtj5SptfQKSLMLTeig1Soh5ULEzQrUI2ff3GRz0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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