SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86e0e2ea0e698cdae68189e0c4bfd0a9b1040722028bb33caddaaf79acbf69ff' 
  AND token = 'tsMaAK3oIuOAApbjzkkN6LuiWMQmRv4u3qQ8tBhw9Sk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00114

JSON explain

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