SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92880a4016c69b2ea6af30e3549da1d23b482789af1f8d34f3ea554b14a93246' 
  AND token = 'jl0g40M02sGgab9laoGT42WUO7GvhoE8N2UAP03zYkU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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