SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abc3d18676689aa773de59b3cd279f7bd01563e7d00bdec8dd71be6043f8567c' 
  AND token = 's1ea/U0klX0eqys2QBMRlGtqLITYfT2Uo95qXbTlteQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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