SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91546ed81fbc865867bb8a2a54b1cbaa0b1a2dd5bcea9d83482ca31604e84737' 
  AND token = 'G477PPjDzuOmGubXWAwez15z1B0fj5KjbTl8a0TTo3M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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