SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fbe25dd76407192d3f958b96477a0f204376e6dc3f187b17c9789a2ccaf6be3f' 
  AND token = '+igdSNBxurp7kBN3TTmmEt+gNXLlaqKBEGahVLo65HY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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