SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd7473ecb1b243d71ad03d0b6ddb43a4e2c5a5bdd9f6791fc658687b8bc8203a' 
  AND token = '/1v8KPeGJZReizjYYah4X7FWtKYPmv+VWRjAzetaUCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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