SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b274e2d1ecf5cdef5bc1c47073d2e08658ffd7f70bddcf1dc5fed96dea130994' 
  AND token = 'AzuBq1kzuggly/EfMm5un4M68C6VFhxsPB+JcLJemYw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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