SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0e480d556fe1cac7e142755fab59abd05925424af2dfb787d0b71e06bfa04b1' 
  AND token = 'OrBWEOazanksyWFlIz8+ym/0u+Vne8qhjzwPSDAgDoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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