SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '15f8daf0400f06020b114b7e932ed0f7d1c11946698695b68a3460e032989501' 
  AND token = 'nxOuIqUxpfydg1Gbax4AVyC1IzytGA5tc7wjjGU6qZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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