SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '940a84d622fdb65fb5907e9b5cb00e98a058bc6deed19c92b694506dc1a9e47a' 
  AND token = 'If8s6GpeHTn8sJuvq8XZomUHp2cMKo7IG/I57hKJz1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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