SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1bdfc36521f76d8a171278246ae87e93f51cb698b4b28872e036760ea0844bf' 
  AND token = 'zOiDGtq3cB7lLVNRNV5f0uG8QoPw9eia4W6sk11yr84=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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