SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7ec3eeca39da407389cca1ec8fa1a3500a1913326f89d007cd5d3b36ac3a4af' 
  AND token = 'DMxOfXbFwAdO5epoSgnKk+wg9LHaas7LumqzkZTqDyk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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