SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '163202da8cbf4984652b2f5380552cf02e349091cfd307e56346b0bd9360ad0c' 
  AND token = 'u0V0JMkimzaDWkhYmCXHCZOsSB76/YRi+GZRCTnGM1s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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