SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be11da6cd25b7196dc5bd069132516b33399fc56866e93fac19fb169467e2368' 
  AND token = 'iNxC+LXNgTyMpPoBEF0jWMMrzu1GrbcckENmiBPKxPQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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