SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8ddb3d75e46a01226fbd454c7afecb826f7f106d94c8c35783e51dc1261d1f8' 
  AND token = 'InhESQsTQwGFg8nME42G3gtXNpKKze/S7RUeKSvdiPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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