SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a403e07dd7a44e26c8e1332833071c124aef9f978884272f9bab3ba184df8bd' 
  AND token = 'F+DAQSFyHVQxXtuLnD92/zA0AvsxRODPr5xEqepYVUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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