SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc2899a22382f2796cbf6c956d6744d38aba59d721d4b47fac655326e043c0ef' 
  AND token = '80nNo8YNnxZfQsxZtVj3y1r4wzBE0kQ8RCXicPD7jVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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