SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b593b32e50aa61bc2f40d7d0eade7b9b331bb2be8717dae8f60243342cca6ea8' 
  AND token = 'erTciTjVo0MYFtHreG/dGhmffsj1bDe3GYkDKLLtcTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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