SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aea7d74a30136c39bf9f2e400aa5299fafdfbb1954064cb80e14c49ac5cfdbed' 
  AND token = '+rLY6LdDQOmF5t0mf2c2pK1d1+juKEIu08JmorrpfqI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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