SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49f6a17aa35c0763ac5780001ac90a5aa5eab631db1c979ced2977a39aada869' 
  AND token = 'W4RzMHNxiT0qQUpn0m9FkV1AbAEOQ5y5MBiyHje8xww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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