SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '693a21b52f36925fce864612cbab2e0df4f6762b22dab27f32e42e420ecf4599' 
  AND token = 'ZW7RREm5DGOsF38B4KFv3QY7wk95VcNDqgcBn86enGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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