SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b9184701c914829831d72fe727084861f1e61c8df304e6dfb4ca00f9eb68893b' 
  AND token = 'lt9l2MM0pQvdhPBK2Jj7yCTI4B+ZWgRutgRQHyvIKw4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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